ИСТИНА

West Siberian landscapes are dominated by poorly drained flat areas suppressing growth of forests. Recent availability of the Landsat imagery from USGS provides opportunity for widescale application to mapping of the poorly accessible regions of West Siberia. Application of Landsat imagery to mapping forest and wetlands are reported. The Landsat-based NDVI maps appear promising for delineating productivity classes in the low productivity middle taiga forests. West Siberian wetlands are world largest in area and contribute essentially to the global methane emission. To calculate the regional methane flux, appropriate wetland map is required. The map by Romanova et al. was the most detailed among whole region wetland maps therefore it was used in CH4 emission inventory. However it provides only aggregated classes and often does not match with field survey data. In this study, we tried to develop a new wetland classification based on Landsat 7 imagery for West Siberian middle taiga and use it for scaling up methane emission observations in the area. It was confirmed that raised patterned ridge-hollow landscapes prevail in middle taiga zone covering more than 50% of its territory and accounting for about 50% of the total methane emission. Pine-shrub-sphagnum complexes take the second place covering a quarter of the mire area. Despite of the huge area they emit only 1% of the regional CH4 flux annually. The rest of territory is mainly occupied by fens, poor fens and swamps (14%) accounting for about 35% of the total CH4 flux. Generally, applying the new map gave 94% higher methane emissions from the middle taiga zone as compared with the map by Romanova et al.